Cylinder ridge reamer



July 31, 1945. w. F. MITCHELL CYLINDER RIDGE REAMER Filed Oct. 2,1942 2 Sheets-Sheet l v i INVENTO-R.

BY fi e W July 31, 1945., w rrc v 2 380,605

I CYLINDER RIDGE REAMER Filed Oct. 2, 1942 2 Sheets-Sheet 2 IN V EN TOR.

Patented July 31, 1945 IUNITED STATES PATENT OFFICE CYLINDER RIDGE REAMER Wallace F. Mitchell, Chicago, Ill., assignor to Automotive Maintenance Machinery (30., North Chicago, 111., a corporation of Illinois Application October 2, 1942, Serial No. 460,517

7 Claims.

My invention relates generally to tools for truing up worn cylinders and it has to do-particularly with a so-called ridge reamer adapted for the removal of circumferential ridges formed by wear occasioned by movement of piston rings along a cylinder wall surface.

It is well known that piston rings tend towear away the cylinder wall surface throughout their range of travel, the upper limit of such travel being below the top of the cylinder so that the wear occasioned by the rings leaves a ridge surface around the top of the cylinder. This ridge will be referred to at times as a ring-wear ridge. In the reconditioning of cylinders it is desirable that this ridge be removed; otherwise, when a new and unworn square-edge ring is installed the upper edge of the ring may strike the ridge and produce a sharp clicking sound. While this action is not at first objectionable from proper ring-seal standpoints it causes increased and rapid wear of the rings with the result that they break down and cease to function properly in a comparatively short time.

It is also well known that cylinders, at the points of wear, tend to wear to a greater extent on one side of the center line than on the other and may wear in an oblong shape. For this and other reasons well known to those skilled in the art, the above-mentioned ridge may be of irregular shape and depth which presents a problem in removing the same. v

One of the objects of my invention is to provide an improved tool of the foregoing character which is of simple and sturdy construction and which is adapted for. removal in a rapid and highly efflcient manner of ridges formed in cylinders by ring wear. 7

Another object is to provide a ridge reamer having a cutting blade which is automatically fed in cutting direction.

Still another object is to provide a ridge reamer of the foregoing character having provision for limiting'the extent of the cutting action.

Other objects are to provide adjustable stop means operable under' the control of the cylinder wall surface for determining the extent of cut of the reamer and to insure complete removal,

01' a ring-wear ridge regardless of variation in depth of the same; and to provide an automatically fed reamer blade having an adjustable stop thereon which is aligned with its ridge cutting edge and adapted to engage the cylinder wall to cause the blade to remove the ring-wear ridge flush with the adjacent cylinder wall surface.

Other objects and advantages will become apparent as this description progresses and by reference to the drawings wherein,

Figure 1 is an elevational view of one form of tool embodying my invention, the same being shown applied to a cylinder having a ring-wear ridge of uniform depth to be removed;

Fig. 2 is a section taken substantially on line 2-2 of Fig. 1;

Fig. 3 is a section taken substantially on line 3-3 of Fig. 2;. V.

Fig. 4 isa section taken substantially on line 4-4 of Fig. 1;

Fig. 5 is a sectiontaken substantially on line 5-5 of Fig. l; I

Fig. 6 isa longitudinal sectionaliviewtaken substantially on line.6--6 of Fig. 4;

Fig. 7 is an enlarged fragmental view showing the reamer blade of the tool of the previous figures in pOsition for removal of a ring-wear ridge;

Fig. 8 is a view similar to Fig. 7 and showing the reamer blade in position after removal of the ridge of Fig. 7; and

Fig. 9 is an enlarged fragmental view showing in full and dotted lines the tool of the previous figures in position in a cylinder ready for removal of a ring-wear ridge of varying depth.

In the drawings, I have shown my invention applied to a. tool adapted particularly for the removal of a ring-wear ridge In (Figs. 1, 6, 7 and, 8) formed in the cylinder ll of an internal com-- bustion engine; however, it is to be understood that my invention has utility in any instance where similar problems and conditions of use are involved. For the purpose of explanation the ridge I0 is shown in Fig, 1 as of uniform depth and in Fig. 9 as of varying depth.

The tool illustrated embodies a supporting section A which is adapted to be mounted in the cylinder II below the ridge Ill so as to rigidly support the tool as a whole therein. It also includes a reamer section B which is rotatably carried by the supporting section A, the reamer section in cluding a cutting blade l2 which is adapted to engage the ring-wear ridge llland remove the same as the reamer section B is rotated.

The support section A includes a top plate l3 (Figs. 1 and 6) having a tubular cylindrical extension I4 on its upper side. A plurality (preferably three) or depending posts l5 are rigidly secured at their upper ends, as at IE, to the top plate l3, which posts pass through openings in a movable bottom plate H to guidingly center and support the same. The posts l5 define radial passageways (Fig. 5) in which are disposed bladelike support members l8 (Figs. 1, 5 and 6), the

upper edges |8 of which are snugly and slidably received in radially directed grooves |3 in the lower side of the top plate |3. The bottom plate It is provided with a plurality of radially directed grooves H which are aligned with the top plate grooves |3 in which the lower and inclined edges |8 of the support members i8 are received. The bases of the grooves H are tapered upwardly and inwardly for engagement with the complementally shaped edge portions |8 of the support members IS.

The support members l8 (Fig. 6) are expansible and contractible to engage the support section A with and release it from the wall of the cylinder II and, to this end, the bottom plate I1 is shifted axially of the tool. Upward movement of the bottom plate l'l, because of the complementally tapered surface of the bottom plate groove I1, expands the support members l8 and this expansion movement is yieldingly opposed by a garter spring |9 (Fig. which tends at all times to urge the support members IS in a contracting direction so that when the bottom plate I! is moved downwardly the support members are contracted to release the tool from the cylinder. Movement of the bottom plate H in opposite directions is accomplished by an adjusting stem 20, the lower end 20 of which is threaded to engage a threaded opening H in the bottom plate H. The stem 20 extends upwardly and rotatably through an axial opening M in the end plate extension I4 and outwardly therebeyond to receive an adjusting nut 2| which will be described further hereinafter.

The end plate extension M (Fig. 6) rotatably supports the reamer section B. This reamer section comprises a body 22 having an axial bore 22 in its lower end in which the end plate extension I4 is rotatably received. Tensioned rotational movement of the reamer section B upon the extension H is provided by a spring-pressed ball 23 carried by the body 22 and engaging a circumferential groove 24 in the end plate extension I4. The body 22 is further provided with a reduced axial bore 22 connecting with the bore 22 and through which the outer end portion of the adjusting stem passes, the body being further provided with an enlarged cage-like head 22 having an enlarged transverse slot or opening 25 in which the adjusting nut 2| is rotatably confined against longitudinal displacement. This adjusting nut 2| is secured to the upper or outer end of the adjusting stem 20 by a pin 26 (Fig. 6). The adjusting stem 2|) is confined rotatably between the body 22 and the end plate extension M by a collar 21 pinned thereto as at 21 and located in the bore 22 at the outer end of the end plate extension l4. With this arrangement the adjusting nut 2| may be rotated in opposite directions to rotate the stem 20 without longitudinal displacement thereof to move the bottom plate l1 up or down to expand or contract the support members l8. The reamer section A is rotated independently of the adjusting stem 20 and nut 2| to effect the reaming operation. The reamer section B is preferably rotated by hand but, if desired, any suitable power means may be employed. As shown in the drawings, the upper end or head 22 of the reamer body is provided with an outwardly extending rectangular shank 28 to which any suitable tool, such as a wrench, may be applied for rotating such body.

Only one cutting blade I2 is employed (Figs. l4), the same being supported by the rotatable body 22 in such a way that the blade cuts with a so-called drag-cut or scraping action thereby eliminating chatter and any dig-in tendencies and providing a smooth and clean cut. The blade |2 is so mounted and actuated that, during the reaming operation, it is automatically fed toward the ridge to be reamed so that repeated adjustment of the blade is not required in order to completely cut away such ridge. It is desirable that the ridge be neither undercut nor overcut, and to insure the cutting away of the ridge to the proper extent, namely, flush with the cylinder wall surface therebeneatl., my invention provides means cooperative Witll the cylinder wall beneath the ridge In (or 45---45 Fig. 9) to limit the extent of feed of the cutting blade and, in turn, the depth of the out. This arrangement is such that even though the depth of the ridge to be cut may be varied, the cutting action will be such that the ridge will be out down flush with the cylinder wall throughout the circumference of the cylinder.

To the foregoing end, the cutting blade |2 is supported in a transverse slideway 29 (Figs. 2-6) formed in the body 22 to one side of and tangentially of the axis thereof. To permit assembly and removal of the cutting blade the outer part of the slideway comprises a removable plate 30, the lower end of which is confined in a groove 3| (Fig. 2) and the upper end of which is secured in place by a screw 32.

Adjustment and feed of the cutting blade |2 is provided for in the manner which will now be described. The inner face of the blade I2 is provided with a diagonal groove 33 extending upwardly and rearwardly from the forward end thereof. Expansion and contraction movements of the blade are accomplished by an actuator unit which comprises a vertical slide member or actuator 34 of general semicircular shape mounted in a similarly shaped slideway 35 (Figs. 2 and 6) located inwardly of and extending downwardly along and above the blade l2. The lower end of slide member 34 is provided with a cam or lug 36 shaped oomplementally to and fitting snugly in the blade slideway 33. It will thus be seen that by moving the slide member 34 upwardly so that the slide cam 36 approaches the rear or upper end of the blade groove 33, the blade I2 is displaced outwardly; and when the slide member 34 is moved downwardly so that the cam 36 approaches the forward end of the slide 33, the blade I2 is retracted.

Movement of the slide member 34 and blade |2 in initially setting the tool in a cylinder for the reaming operation may be accomplished manually, the actual movement of the slide member 34 and feed of the blade during the reaming operation being accomplished automatically. Specifically the upper end of the slide member 34 is provided with a threaded extension 31 which projects upwardly and outwardly beyond the slideway 35 where it receives an adjusting abutment or nut 38. The upper end of the slideway 35 is covered by a washer-like closure 39 having an opening through which the threaded stem 31 freely passes. A spring 40 is confined between the outer end of the washer 39 and the adjusting nut 38. The reamer body 22 is provided with a recess or well 4| immediately beneath the cagelike head 22. The slide member stem 31 projects'into the well 4| so that the nut 33 is disposed therein with the underside of the body head 22 serving as a stop abutment limiting the upward or outward movement of the nut 38. The

ass con springzll fliiSiSOZ constructed; thatiitis undenslight. tension when; the; nuts 3:8:1 abuts: the; head-22;

With;- the: foregoing. arrangement. assuming thatrtheztoollisain,positiominiaicylinden, asshow-n. in; Fig; I; and; it; iSi desired to'iretractrthe; cutting blade; the adjusting; nut 3isa rotated: iniaa 0.011111- terclockwise; direction; until; its upper. end abuts tin; head 229 ofjthe: body; 22.: Further rotation of. the: nut;38; will.then;move the slide; member. 34 and; its feather 36 downwardly; to. retract the. blade, .as "ahovaexplaineds Conversely; when itis desired to; expand the blade from its; contracted condition, the nut 3llsiscrotatedzini a; clockwise direction, thereby drawing. the slide 342 and its feather:- 35; upwardly.- to; move: the blade; I2: out- Wardlytx 1 v IXLUSB, assuming; that a ridgeclfl; suchzasshown inzFig.-: 1-, isnto'be removed; the tool is first applied toz'the.cylinder'with'the support members disposed .belowqtheridge I The adjusting nuti2 l: isithen' rotated; in. aiclockwise direction to move the bottom: plate L1 upwardlyand expand the support; membersl8 into firm engagement with the cylinder-wall. After, this-the-nut 38 is first manuallyv rotated" in aclockwise direction to expand the bladel-zzto'engage-itscutting edgelZ with -the ridge- I0; After thebladeisengaged with :the ridge H] the nut 38', preferably, isfurther rotated sufficiently to completely compress= the spring-40 and is their backed off, so'to speak; one or twoiturnsz In this way the nut 3'8 is moved away from the body head 22 permitting-"upward movement thereof to expand the blade andthe spring 43 isplaced under compression and conditioned to yield'ably urge the slide 34' and its feather'iifi upwardly to=move -the cutting blade I2 outwardly inexpanding direction. With the blade [2 so setawrench or other tool is applied to the shank 23- to rotate the reamer section B' and, asthis takes place, the-blade lz'cuts away the ridge ID, the blade automatically expanding as the metal is cut away to completely'remove the ridge- -l 0;

A's-above pointed out; it-is highly desirable that the ridge l0 be cut away: toan extent flush with the cylinder wall surface therebeneath. It will be" appreciated that it I would I be extremely difli cult, and impractical, for an operator to attempt try-determine, while-rotating-the tool, just when that flush condition=is reached so that, unless otherwise-provided against, the ridge maybe cut awaytoo much ortoo little with resultant deleterious efiects well recognized by those skilled inthe art. To'guard against this my invention provides stop means which prevents further reamingwhenthe=ridgeis cut away flush'with' the cylinder wall therebeneath.

More particularly, the cutting edge [2 terminates short of the lower edge of the blade l2 providing a notch forming a land or ledge 42 (Figs. 1, 3, 7-9) at the lower forward edge of the blade I2 adjacent the wall of the cylinder II. On the ledge 42 I provide a stopmember 43 which takes the form of a screw engaging in a suitably threaded opening in the-ledge 42. Theouter end of, the screw- 43 is provided with a rounded or hemispherical button-like end 43 inwardly of which is a hexagonal or other suitably-shaped portion 43 which may be eng-aged to screw thesamerinto the.ledgeiopening. The screw is secured in adjusted" position by a lock nut 44.

In use, the stop member, is adjusted to a position wherein the outer surface of its buttonlike end 43 is in vertical alignment with that portion of the blade cutting edge I2 which will en age theilowerronrbottom"; edge of thezri'dge; I'll; It; will beinotedi thatththez'cutting edge: mi -of the blade; I2 is slightlyftapered downwardly/endinwardly (preferably 3i 2? taper) so: as to 7 cut: away the; ridged: portion of the cylinder on. a slight bevel;v I havezfoundin practice:thatiexcellent resultsmay be obtained. by positioning the" toolin thev cylinder to sllohfiadepth that the buttoip-like end of .the/stop vmembern 43isiapproximately onequarter of an inch blow the lower edge of; the ridge I it; It will be seen tha-tzwith this arrangement, as soon 1 as: the lower edge. off the ridge I 0 iscutz away; (Fig; 8): toaniextentiwh'ereini itr is flush with the 1 cylinder: wall; the; stop member? 43 engages the cylinder walhthereby preventing: fur-- ther expansion." movement of the cutting blade 12: and,.in' turn; further: reaming of the cylinder. sur- I face The-head or: end 43 of the screw, being ing by the tool due to such wedging is avoided:

It 'will benoted that; since -the-screw 43 isat the outer end 'ofthe blade, the screw'may be adjusted without-riecessitat'ing removal of i the blade from the bedy-member.

The; fore-going arrangement, including the automatically fed cutting" blade and I the; stop means limiting theie'ed of the blade,- enables one to cut away aridge caused" by ring wear uniformly throughout itscircumference, notwithstanding the fact thatsuch ridgemaybe of varyingdepth; ashereinabove explained Suc-h'a ridge isshown at 45 and 45 in Figs 9, the ridge portion 45 being of greater depth than theridge portiont ts Invi'ew'ot the faot that: the automatic feed of the cutting blade will take pl-aceand the' 'reaming operation will continue untilthe' stop n-lember 43- engages the" cylinder wall throughout its circumference, the: reaming operation, while stopped at 45 (Fig. 9), will-continue at 45* (Fig; 9) and at points .therebetween. As soon as the stop member 43-contactsthe cylinder throughout itscircumference, which action can readily be-felt by the-operator, the-reaming"- operation is co1nplete; no further material will be removed, and the .tool may beremoved from the cylinder. When so removed, outward movement of the blade is limited by contact of the'nut 38 and the head 22.

I believe that the operation and advantages of my inventionwillbe obvious from the foregoing description; My'invention not only provides a very simpleand 'sturdy' tool for the purpose stated, but it also provides a tool wherein theridge'ream ing' operation may be carried on more quickly thanheretofore and with'greater accuracy. My invention also insures-more 'eificient reconditioning of worn cylinders at less expense. It also'pr'ovides a tool which maybe used with the desired accuracy .by'unskilled labor without danger-of It over=reaming or under-reaming the .ridge; also" provides an" arrangement wherein difierent portions of the cuttingedgel 2 maybe employed sharp part of the edge may be used. In that case, and to accommodate the different depths of the tool in the cylinder, due to the taper of the cutting edge 12 the stop member 43 may be adjusted so as to properly align with that portion of the cutting blade which will engage and cut the bottom edge of the ridge, thereby preventing the blade from cutting to an extent deeper than the cylinder wall surface below the ridge.

I claim:

1. In a tool adapted for removal of ring-wear, or the like, ridges formed on the wall of a cylinder, a body member, means for supporting said body member for rotational movement, a cutting blade slidably carried by said body member for substantially radial outward expanding and inward contracting movement and having a cutting edge on the outer end thereof, means for automatically feeding said blade outward to cut away the ridge, said blade having a notch cut in its lower outer corner, a round-headed screw located in said notch and threaded generally radially into said blade with its head outward to contact the cylinder wall beneath the ridge to limit the expanding lock nut on said screw to lock the screw with its head in alignment with the cutting edge of said blade to limit the cutting action to removal of the ridge.

2. In a tool adapted for removal of ring-wear, or the like, ridges formed on the wall of a cylinder, a body member, means for supporting said body member for rotational movement, a cutting blade slidably carried by said body member for substantially radial outward expanding and in- Ward contracting movement and having a cutting edge on the outer end thereof, means for automatically feeding said blade outward to cut away the ridge, and a screw threaded generally radiall into said blade with its head outward to contact the cylinder wall beneath the ridge to limit expanding movement of said feeding means, the head of said screw being generally hemispherical to provide substantially point contact with the cylinder wall and toprovide a rounded upwardly facing surface of relatively small dimension to prevent chips from collecting on said head and wedging between said screw and the cylinder wall.

3. In a tool adapted for removal of ring-wear, or the like, ridges formed on the wall of a cylinder, a body member, means for supporting said body member for rotational movement, a cutting blade slidably carried by said body member for substantially radial outward expanding and inward contracting movement and having a cutting edge on the outer end thereof, means for automatically feeding said blade outward to cut away the ridge, and a round-headed screw threaded generall radially into said blade with its head outward to contact the cylinder wall beneath the ridge to limit expanding movement of said feeding means, said screw being positioned with its head rearwardly of the cutting edge of said blade whereby the chips will fall clear of said screw.

4. In a tool adapted for removal of ring-wear, or the like, ridges formed on the wall of a cylinder, a body member, means for supporting said body member for rotational movement, a cutting blade slidably carried by said body member for movement of said feeding means, and a substantially radial outward expanding and inward contracting movement and having a cutting edge on the outer end thereof, means for automatically feeding said blade outward to cut away the. ridge, and a stop member mounted on the outer end of said blade to contact the cylinder wall beneath the ridge to limit expanding movement of said feeding means, said stop member being adjustable relative to said blade and accessible for such adjustment at the outer edge of said blade whereby such adjustment may be made when the blade is assembled in operative relation with said body member.

5. In a tool adapted for removal of ring-wear, or the like, ridges formed on the wall of a cylinder, a bod member adapted to be supported for rotational movement, a cutting blade slidably carried by said body member for radially outward expanding and inward contracting movement, and spring-loaded means carried by said body member for automatically feeding said blade in an expanding direction, said means extending upwardly above the cylinder and having means for adjusting the spring pressure located above the cylinder for convenient adjustment when the tool is positioned within the cylinder.

6. In a tool adapted for removal of ring-wear, or the like, ridges formed on the wall of a cylinder, a body member adapted to be supported for rotational movement, a cutting blade slidably carried by said body member for radially outwardl expanding and inward contracting movement, an actuator for said blade mounted in said body member and having a threaded end portion, said body member having a recess into which said threaded end portion extends, a spring surrounding said threaded portion and held by said body member against movement at one end, and a nut on said threaded portion and bearing against the other end of said spring to place the latter under compression, said nut being adjusted on said threaded portion so that, when the blade is in engagement with the cylinder wall, the nut is held in spaced relation to the adjacent side of said recess, the nut being adapted to engage said side when the blade is removed from the cylinder to prevent excessive outward movement of said blade.

7. In a tool adapted for removal of ring-wear,

or the like, ridges formed on the wall of a cylinder, a body member adapted to be rotated and having a portion adapted to extend into the cylinder for securement thereto and a portion extending above the cylinder with a recess in said extending portion, a cutting blade slidably carried by said body member for radially outward expanding movement and inward contracting movement, an actuator engaging said blade and movable to expand and contract the blade, a spring mounted on said actuator and bearing at one'end against one side of said recess, and an abutment adjustably mounted on said actuator and bearing against the other end of said spring, said abutment being adjustable in one direction to place said spring under pressure for expanding said blade with said abutment spaced from the other side of said recess and being adjustable in the other direction to bear against said other side of said recess to contract said blade.

WALLACE F. MITCHELL. 

